gardiner



P. G. GARDINER.

Carriage-Spring.

' Wiinesses=' M lnventon AM- PHOTO-LITNO. Q0. N.Y. (OSBORNE'S PROCESS.)

UNITED STATES PATENT OFFICE.

PERRY G. GARDINER, OF NEW YORK, N. Y.

, CARRIAGE-SPRING.

Specification of Letters Patent No. 31,881, dated April 2, 1861.

To all whom it may concern:

Be it known that I, PERRY G. GARDINER, of New York, in the county and State of New York, have invented a new and Improve Spring ;"and I do hereby declare that the f llowing is a full and exact description of the same, reference being had to the accompanying drawings, and to the letters of reference marked thereon.

Figure I represents a side view of my improved spring in its natural state and Fig. II shows a spring when under weight or compressed.

The nature of my invention consists in the combination of two steel blades, bent in different curves and connected together at their ends for the purpose of producing a stronger spring by a diminution of material.

In the manufacture of my improved spring the two blades are turned on their ends, so as to fit one into the other and to form a hole through which a bolt or pin, '0, is passed, with large heads, covering the ends of both blades, so as to prevent any lateral motion. I visable to make both blades exactly the same length, but in some cases the lower blade may be made a little longer. I likewise prefer to make the lower blade lighter or thinner than the upper blade but both blades are made thickest in the middle, tapering gradually toward both their ends.

The top blade A is bent then in an arched or elliptic curve, while the lower blade B is bent in a wave line curve having the end curves alike to each other and forming parts a of an arched curve while the central part of said blade forms an inverted arch. The shape of said lower blade B may likewise lie-called a combination of two cima or ogee curves arranged so that the central or middle part shall form an inverted arch.

The weight or load being applied in the center on both springs, the tendency of the top blade A would be to flatten out, while the action of thelower blade B, where the I likewise prefer and find it ad' weight is applied against the inverted arch, will draw the'ends toward each other, and at the same time bring the arched end parts against the top blade A. By this action the two blades form braces to each other, and

as the increase of the weight or load against the springs will cause the end parts of the lower and upper blades to lie more and more upon each other, changing thereby constantly the point of motion, and at the same time changing the elfective length of the spring I obtain by this arrangement a spring which by a very light weight is easy and sensitive, and increases gradually in strength and stiffness in direct proportion as the weight or load on the spring increases.

The above described action, resulting from the combination of two blades, bent and connected together, as heretofore stated pro duces not only, by a weight of metal less than ever before attempted, a spring superior in strength and elasticity and capable of graduating itself to the load, but any crystallization of one point more than any other point is thereby prevented, and whereby this improved spring will be more durable and less liable to the danger of breaking.

lVhat I claim as my invention and desire to secure by Letters Patent is- 1. The construction of a carriage or other spring, substantially as herein described, by combining with an upper elastic blade of a convex form outwardly, an ogee-shaped under blade, in the manner and for the purposes set forth.

2. In combination with a spring made of two blades connected at their ends, as shown and described, I claim making the underblade of such length in relation to the upper, as that the two blades shall be prevented from coming in contact at their centers, whatever the superincumbent weight or load may be.

P. G. GARDINER.

Witnesses HENRY E. BOEDER, Z. G. WHEELER. 

